Background Medication errors have long been associated with low-quality medical care services and significant additional medical costs. Objective The aim of this study was to culturally adapt and validate the questionnaire on knowledge, attitudes and behaviors in the administration of intravenous medication, as well as to explore these factors in a hospital setting. Methods The study was divided into two phases: 1) validation and cross-cultural adaptation, and 2) cross-sectional study. A total of 276 hospital-based nursing professionals participated in the study. Results A Cronbach’s alpha value of 0.849 was found, indicating good internal consistency. In the multivariate analysis, statistically significant differences were found between knowledge and attitudes, demonstrating that having greater suitable knowledge correlates with having a more positive attitude. It was also discovered that having a positive attitude as well as the necessary knowledge increases the possibility of engaging in adequate behaviors. Conclusions The knowledge, attitudes and behavior questionnaire has a satisfactory internal consistency in order to be applied to the Spanish context. Implications for nursing management: Knowledge acquisition and positive attitude are both factors which promote adequate behavior, which in turn seems to have an impact on medication errors prevention. Health institutions must encourage continuous education for their employees.